Light transmission mechanism



5 2 Nov; 11-,1952 P WE S Em 2,617,892

LIGHT TRANSMISSION MECHANISM Filed Sept. 9, 1950 2 SHEETS-SHEET l NVENTORH, e/a/m 5" owe/s and ((Ja/t'f 19. L021;

BY %2M 5% Nov. 11, 1952 J. 5. POWERS ETAL 2,617,892

LIGHT TRANSMISSION MECHANISM Filed Sept. 9, 1950 v 2 SHEETS-SHEET 2 TZe/r fitter/243 Patented Nov. 11, 1952 TENT OFFICE LIGHT TRANSMISSION MECHANISM Applicationiseptember 9, 1950,'SerialNo. 1839584 4;.Glaims.

This inventionirelatess-toizcertain :new and usefulimprovements: in light transmission mechanism fcr anexciterlightlof a 'motion pictureap- .paratus :andhas for. its principal. obiectxthe provision of. an. improved; constructionyof this character which will: be highly efficient iinlzuse and economical manufacture.

.One. of the; principal objects of: thisinvention is to provide an arrangement for'concentrating lightsfromxan exciter light on the photo-cell of a motion :pictureyapparatus whereby to obtain the highest degree of perfection of sound reproduction.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of parts to be hereinafter described and .claimed.

Theinvention will be best understood by reference to the accompanying drawings showingqtthe preferred. form of construction and in -which:

Fig. 1,.-is.a fragmentary .elevational view of a motion picture sound reproduction apparatus with which our invention is associated;

Fig. 2 is a top plan view of the same;

Fig. 3 is a side elevational view of the same;

Fig. 4 is a perspective view of the light transmitter embodied in our invention;

Fig. 5 is an enlarged plan view of the same partly in section;

Fig. 6 is a longitudinal sectional detail view of i the same;

Fig. 7 is a sectional detail view taken substantially on line of Fig. 5; and

Fig. 8 is a fragmentary sectional detail view of the outer end of the transmitting mechanism showing the same in relationship to a scanning device.

In the drawing the motion picture sound reproduction apparatus is indicated at I0. On the front wall of such apparatus is mounted a lamp housing including an exciter lamp l2 and a scanning device l3. This scanning device I3 confronts the sound track of the film web I l as it passes over a sound drum l5. This sound drum I5 is rotatably mounted on a shaft I6 which passes through a bearing sleeve l1 mounted from the wall I8 01 the apparatus H). To the inner end portion IQ of this shaft is mounted a driven member 20 through the medium of which the shaft I6 is rotated.

The bearing sleeve ll provides a bearing head 2| within which a suitable roller bearing 22 is arranged for the inner end portion of the shaft I6.

At the outer end portion 23 of the sleeve I1 is arranged a roller bearing 24 for the shaft I6.

The sleeve .il provides -an -elongated' sl'ot'fi. Positioned .in this slot is a shaft 26 preferably ,formedofcrownglass andtapering on three sides thereof in. the direction of its longax-is in a direction toward thephoto-cell '43.

Thisilightshaft with the eXception-of'its opposite extremities: is enclosed within an enclosure .2?- preferably comprising two confronting plates 2.8 :and 29 .havingxarranged' therein confronting channels 38. These .plates are secured together towtheshaftrlat by means of screws 31. The shaft-Ztfis snuglyamounted in this enclosure upon a:fi1ler;:strip.32 and between filler strips 39. The entire area of the -shaft.26 with the exception of the extremities of the outer surface All is covered by preferably a black lacquer.

These uncovered areas are "indicated at- H and By thus covering the surfacesof the -shaft 26 except for thearea-s indicated at 4 I. and-42 no light traveling :through atheshaf-t can filter from .O1:p118tl2;t8.th shaft exceptuthe. uncovered areas ll and 42 of the surface 46.

It will be noted that the surface 4| is substantially larger than that of the uncovered surface 52. This surface M is disposed in alignment with the scanning device l3 and has concentrated thereon the light from the exciter light I2. The smaller area 42 confronts the photo-cell 43 which is mounted upon a structure 44 to the rear of the wall of the apparatus I I].

The shaft 26 at its end portions opposite the areas 4| and d2 provides right angular deflecting surfaces (l5 and 46 respectively. These surfaces are covered with a covering similar to that covering the other surfaces of the shaft 26. V

A light beam from the exciter light l2 will be concentrated by the scanning device [3 upon the area 4| and be deflected by the deflecting surface 45 in the long direction of the shaft 26 at the end of which long direction the light beam will be deflected by the deflecting surface 46 for concentration upon the photo-cell d3. By this arrangement the full light value from the exciter light is concentrated on the photo-cell resulting in the maximum perfection of sound reproduction.

While we have illustrated and described the preferred form of construction for carrying our invention into effect, this is capable of variation and modification without departing from the spirit of the invention. We, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail ourselves of such variations and modifications as come within the scope of the appended claims.

Having thus described our invention, what we claim as new and desire to protect by Letters Patent is:

1. A device for transmitting light from an exciter lamp of a motion picture sound reproducing apparatus to a photo-cell thereof comprising a bearing structure having an elongated slot formed therein, a, shaft journaled in said structure, a sound drum on said shaft, an enclosure mounted on said shaft and positioned in said slot, a shaft of light transmitting material mounted in said enclosure with the extremities thereof projecting beyond the ends of the enclosure, said shaft with the exception of the outer surface of the said extremities being enclosed in a light impenetrable material, one of said'extremities being adjacent said sound drum in confronting relation with respect to the exciter lamp and the other extremity of said shaft being in alignment with the photo-cell.

2. A device for transmitting light from an exciter lamp of a motion picture sound reproducing apparatus to a photo-cell thereof comprising a bearing structure having an elongated slot formed therein, a shaft journalled in said structure, an enclosure mounted on said shaft and positioned in said slot, a shaft of light transmitting material mounted in said enclosure with the extremities thereof projecting beyond the ends of the enclosure, said shaft with the exception of the outer surfaces of said extremities being enclosed in a light impenetrable material, one of said extremities being in confronting relation with respect to the exciter lamp and the other extremity of said shaft being in alignment with the photo-cell.

3. An optical system for transmitting light from an exciter lamp of a motion picture sound reproducing apparatus to a photo-cell thereof comprising a bearing structure having an elongated slot formed therein, a shaft of light transmitting material carried by said structure in said slot, a light-impenetrable covering of black lacquer for said shaft with the exception of the opposite extremities of one surface of the shaft, and mounting means for said shaft comprising a light-impenetrable enclosure and filler means of a length less than that of the shaft for mounting the shaft in said enclosure with its extremities extending beyond the opposite ends of said filler means.

4. An optical system for transmitting light from an exciter lamp of a motion picture sound reproducing apparatus to a photo-cell thereof comprising a bearing structure having an elongated slot formed therein, a light-transmitting shaft carried by said structure in said slot, a sound drum on said structure, a light-impenetrable covering for said shaft with the exception of the opposite extremities of one surface of the shaft, one of said extremities being adjacent said sound drum in confronting relation with respect to the exciter lamp and the other extremity of said shaft being in alignment with the photocell, and mounting means for said shaft comprising a light-impenetrable enclosure and filler means of a length less than that of the shaft for mounting the shaft in said enclosure with its extremities extending beyond the opposite ends of the filler means.

JOHN S. POWERS. WALTER A. LOTZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

